What are the common additives used in ink classification?
Quick answer: For practical formulation work, photoinitiator screening starts with the light source and film build, then checks yellowing, adhesion, and cure completeness under real production conditions.
Ink additives are used to adjust the ink to adapt to different printing conditions of auxiliary materials. There are many types of ink additives, generally used to remove the sticky agent, light agent, drying agent, slow drying agent, thinner, friction-resistant agent, varnish, etc. In addition to the above several commonly used ink additives, there are anti-scuffing agent, anti-bubble agent, printing gold oil, etc.. From the perspective of improving the efficiency and quality of printing, according to the changing printing conditions, in the ink selected to add some additives, to ensure that the normal printing is beneficial.
Withdrawal adhesives: Withdrawal adhesives have a very small viscosity, generally used in lithographic and letterpress printing ink to reduce its viscosity. In offset printing, due to changes in paper properties and printing conditions, such as oil absorption, poor surface strength, front and back of the coating has fallen off, when the desiccant is too much or printing shop room temperature is too low, will cause paper hair pulling, printing pile plate, paste plate and other failures, affecting the quality of the print. Therefore, when the above phenomenon, you can add the right amount of withdrawal of adhesives, it can play a role in weakening, eliminating the above failures.
Withdrawal of light agent: withdrawal of light agent is also known as a washout agent, is a relatively large amount of offset printing additives. There are two kinds of common evacuating agents: one is transparent oil, used for glossy ink; one is resin-based evacuating agent, used for resin ink. If you find that the ink color is too dark in printing can not restore the original, you can add the right amount of light agent to make it achieve the desired effect.
Desiccant: desiccant is one of the very important printing ink additives. According to the different printing conditions and printing paper, the dosage, type and usage of desiccant are also different. The commonly used desiccants are red drying oil and white drying oil, and the drying of red drying oil is from outside to inside, while white drying oil is dried at the same time with outside. When printing, I choose the type of drying oil in accordance with the requirements of drying the print and ink color. Generally the amount of drying oil is 2%-3%, too much will be counterproductive and make the drying speed decrease.
Slow drying agent: anti-drying agent is also called antioxidant, which is the opposite of the drying agent of an ink additive. In the printing process, due to various reasons often cause downtime, when the downtime is longer, the ink on the dry skin. In order to, solve such problems, often to the machine ink to add the right amount of anti-drying agent, and run the machine a few times, so that it does not dry too fast.
Diluent: in printing because of excessive ink viscosity or poor paper quality, etc., often produce paper hair pulling, plate failure, affecting the normal printing, at this time, in addition to adding the appropriate amount of withdrawal of viscous agent to reduce the viscosity of the ink, you can also add a small amount of diluent to reduce the viscosity of the ink outside, so that printing goes smoothly. Diluent of more types, generally low viscosity of the six ink transfer oil.
Friction-resistant agent: friction-resistant agent is also known as a smooth agent, most of these substances to wax-based substances, in the printing ink particles coarse, such as white ink, gold and silver ink, add the right amount of friction-resistant agent to increase the friction resistance and smoothness of the printed material.
Varnish: trademarks, albums and other high-grade prints, most of the print surface to be varnished to achieve a high gloss effect, the use of varnish, can be mixed in the ink before printing, can also be printed in the print after the addition of a varnish. But by the varnish treatment of the print, long after the yellowing, poor light resistance, therefore, there are now many alternatives to the varnish of the new varnish has been applied.
How formulators usually evaluate this photoinitiator topic
When technical buyers or formulators screen photoinitiators, the most useful decision frame is usually cure quality plus application fit: which package cures reliably, keeps appearance acceptable, and still works under the lamp, film thickness, and substrate conditions of the actual process.
- Match the package to the lamp first: mercury lamps, UV LEDs, and visible-light systems can rank the same photoinitiators very differently.
- Check depth cure and surface cure separately: a film that feels dry on top can still be weak underneath.
- Balance yellowing with reactivity: the strongest deep-cure route is not always the best commercial choice if color or migration risk becomes unacceptable.
- Use the final formula as the benchmark: pigment load, monomer package, and film thickness can all change the apparent ranking of the same initiator.
Recommended product references
- CHLUMINIT 819: Useful when a formulation needs stronger absorption and deeper cure support.
- CHLUMINIT 1173: A practical comparison point for classic short-wave UV initiation.
- CHLUMINIT ITX: A useful long-wave support route in many printing-ink packages.
- CHLUMINIT CQ: A direct reference for visible-light and color-sensitive curing discussions.
FAQ for buyers and formulators
Why are blended photoinitiator packages so common?
Because one product may control yellowing or lamp fit well while another improves cure depth or line-speed performance, so the full package is often stronger than any single grade.
Should incomplete cure always be solved by adding more initiator?
Not automatically. The real limitation may be the lamp, film thickness, pigment shading, or the rest of the reactive system rather than simple under-dosage.
Contact Us Now!
If you need Price, please fill in your contact information in the form below, we will usually contact you within 24 hours. You could also email me info@longchangchemical.com during working hours ( 8:30 am to 6:00 pm UTC+8 Mon.~Sat. ) or use the website live chat to get prompt reply.